The question of the need for mechanical treatment of the paintwork coating (LPC) before applying a protective composition worries both beginners and experienced car enthusiasts. Many car owners mistakenly believe that liquid glass or ceramics can hide minor defects, working like a thick layer of varnish. This is a dangerous misconception that can lead to disappointment in the result and a waste of budget on expensive materials.
Ceramic coating, unlike waxes or sealants, creates a thin but extremely durable film on the surface. It does not fill scratches, but only emphasizes the surface relief. If you apply ceramics to an unpolished body, you will preserve all existing defects under a layer of “glass”. They can only be removed later by aggressive polishing, which will remove the ceramic itself, and the procedure will have to start all over again.
In this article we will analyze the technological process in detail, explain the physico-chemical processes of adhesion of the nano-composition to the surface and answer the question of whether it is possible to save money at the stage of paintwork correction. Understand once and for all: surface preparation - this is 80% of the success of the entire procedure. Ignoring this stage turns an expensive procedure into a useless exercise.
Physics of the process: why ceramics do not hide defects
To understand the need for polishing, you need to understand the structure ceramic coating. It is a solution based on silicon dioxide (SiO2) or titanium dioxide (TiO2), which, after application and polymerization, turns into a solid, glassy substance. The thickness of this layer usually varies from 1 to 5 microns, which is disproportionately small for filling even small scratches.
When you look at an unpolished car, you see distorted light reflecting off the rough edges of the paint. Ceramics, when hardened, repeat this relief. Moreover, the high transparency and glossy effect of modern formulations make scratches and holograms even more visible in certain lighting conditions. Depth defects remain the same, and the visual contrast only intensifies.
There is a myth that multi-layer application (2+2) can hide small swirl effects. This is wrong. Each subsequent layer only records the current state of the base. If the base is defective, the final result will look like "sealed dirt" or preserved scratches. Professional detailers always insist on complete one-stage or two-stage polishing before applying protection.
⚠️ Attention: An attempt to apply ceramics to a poorly prepared body will result in all paintwork defects becoming even more clearly visible due to the high light reflection coefficient of the ceramic layer.
What are holograms and why are they dangerous?
Holograms are micro-risks after poor-quality polishing or washing in automatic brush washes. They create a rainbow effect in the sun. Ceramics, having high adhesion, penetrates into these microcracks, and it will be extremely difficult to remove them later without an abrasive.
Preparation stages: from washing to degreasing
The process of preparing the body for the application of ceramics is much more complicated than simply “wash and wipe”. This is a multi-step procedure, where each step is critical to the durability of the coating. Skipping any step puts you at risk adhesion (adhesion) of the composition with the paint coating.
The first step is always a thorough wash, often a two-phase wash using active foam and pH-neutral shampoo. However, regular washing removes only about 60-70% of dirt. The remaining particles are bitumen, metal dust (brake dust), wood buds and industrial emissions that have become embedded in the pores of the varnish. Special chemicals are used to remove them.
Chemical cleaning is followed by mechanical cleaning with clay or a synthetic analogue (for example, Clay Bar). This stage allows you to pull out from the pores of the varnish what the chemicals could not dissolve. The surface becomes perfectly smooth to the touch, which is a prerequisite before polishing. If you skip this step, the abrasive during polishing will simply drag dirt across the varnish, creating new deep scratches.
- 🧼 Deep wash: removal of basic dirt and road dust.
- 🧪 Picking: using an alkaline shampoo or special cleaner to remove old layers of polishes and waxes.
- 🚗 Claying: mechanical removal of stubborn particles of bitumen and metal.
- 🧽 Degreasing: final cleaning with anti-silicone before polishing.
☑️ Body preparation checklist
Paintwork correction: eliminating defects by polishing
It is at this stage that the magic of transforming a matte, time-scratched body into a mirror surface occurs. Correction of paintwork is the process of removing a microscopic layer of varnish (usually 3-5 microns) along with the defects located in it. For this purpose, polishing machines and abrasive pastes of various grain sizes are used.
There are two main approaches: one-step and two-step polishing. One-stage (restorative) polishing is carried out with one paste, which simultaneously removes medium defects and leaves a good gloss. This is often enough for cars with mileage up to 50-70 thousand kilometers, if the body does not have deep damage. Two-step polishing involves working first with a coarse abrasive to remove deep scratches, and then with a finishing paste to create the perfect gloss.
It is important to understand that polishing is the removal of material. The varnish on modern cars has a limited thickness, and this process should not be abused. However, if you plan to apply ceramics, a good polish is a must. Without her hydrophobic effect will work unevenly, and the appearance of the car will not live up to expectations.
Always measure the thickness of the paintwork with a thickness gauge before starting polishing work. This will help determine how safe it is to remove the varnish layer, especially on repainted elements.
Finishing and degreasing before ceramics
Once polishing is complete, the critical step is final cleaning. During the polishing process, dust from varnish, oil from polishing paste and fingerprints remain on the surface. If you apply ceramics to such a surface, it will lie on the oil film, and not on the varnish itself. This will lead to the fact that after a few washes the coating will simply begin to peel off in “stockings” or in spots.
For cleaning, special degreasers (Pre-wax cleaner or IPA alcohols) are used. They dissolve residual oils and provide perfect adhesion ceramic composition. Some craftsmen also use abrasive polishes with minimal oil content ("anti-holograms") to ensure a clean surface.
Do not use household degreasers or alcohol from the pharmacy in their pure form, as they may be too aggressive or contain additives that interfere with polymerization. Professional chemicals for detailing are designed specifically for preparation for the application of nano-coatings. It evaporates quickly and leaves no traces.
| Stage | Goal | Materials | Risk of missing out |
|---|---|---|---|
| Washing | Removing dirt | Shampoo, foam | Damage to the varnish during further processing |
| Claying | Removing inclusions | Clay, lubricant | Deep scratches when polishing |
| Polishing | Troubleshooting | Pastes, circles | Preservation of scratches under ceramics |
| Degreasing | Oil removal | Antisilicon, IPA | Peeling of coating, stains |
After degreasing, touching the body with gloved hands is strictly prohibited. Any touch leaves a trace of fat that will have to be removed again. The room where the application takes place must be clean, free of dust and drafts, so that microparticles do not settle on the sticky layer of ceramics.
The quality of degreasing directly affects the service life of the ceramic coating. Saving at this stage will lead to the need to redo the work in 2-3 months.
Comparison: polished or not
Let's compare the two scenarios to fully understand the difference. In the first case, the owner decided to save time and money by skipping polishing and applied the ceramic immediately after washing. In the second case, full preparation was carried out with correction of the paintwork.
In the first scenario, the car only looks clean for the first couple of days. After the first wash, it becomes clear that the hydrophobe (water rolling off) works unevenly: somewhere the water stands in a “column”, and somewhere it spreads. The scratches have not gone away, but due to the transparency of the ceramic they have become more noticeable. After six months, this coating begins to become cloudy.
In the second scenario, the car shines like new. The color depth increases, a rich “wet” effect appears. Water rolls off evenly over the entire surface, taking dirt with it. The service life of such a coating is stated by the manufacturer (2-5 years), since it is maintained on a clean, prepared base.
- 💧 Hydrophobic: with polishing - stable, without polishing - stains.
- ✨ Gloss: with polishing - mirror, without polishing - matte with scratches.
- 🛡️ Protection: with polishing - durable, without polishing - weak adhesion.
Common mistakes when applying it yourself
Many car enthusiasts decide to apply ceramics themselves by purchasing kits in online stores. However, the lack of experience and special tools often leads to disastrous results. One of the main mistakes is insufficient exposure time or, conversely, overexposure of the composition on the surface.
Another common problem is using the wrong wipes. Cheap microfiber can leave lint or even micro-scratches on the composition that has not yet hardened. The temperature regime is also often ignored: application to a hot body or in direct sunlight leads to instant polymerization, and the composition cannot be spread evenly.
⚠️ Attention: Never apply ceramics in a dusty garage or outdoors. Specks of dust that fall on a fresh layer will harden in it forever, and they can only be removed by machine polishing the entire surface.
Don't forget about ventilation. Solvent vapors contained in ceramics may be harmful to health. It is necessary to work in a respirator and gloves. It is also important to allow the vehicle to dry completely before driving - this usually takes 12 to 24 hours depending on humidity and temperature.
What to do if the ceramics are stained?
If you notice spots (chaotic streaks) immediately after application, try gently polishing the area with a special finishing paste or ceramic remover. If the composition has already polymerized (more than 24 hours have passed), only machine polishing with an abrasive will help.
FAQ: Answers to popular questions
Is it possible to apply ceramic without polishing if there are no scratches?
Yes, if the car is new (only from the showroom) and there really are no defects (cobwebs, holograms, risks). In this case, a stage of deep cleaning with clay and degreasing is sufficient. However, even on new cars there are often transportation defects that are best removed.
How long does it take for ceramics to dry after application?
Primary polymerization (when you can gently touch the surface) takes from 1 to 4 hours depending on the composition and conditions. Complete crystallization and hardening occur within 7-14 days. During this period, it is not recommended to wet the car or use aggressive chemicals.
Do I need to polish my car before using liquid glass?
Liquid glass is a softer and less durable analogue of ceramics (service life up to 1 year). The preparation requirements are similar: polishing is required for an ideal result. If you apply “glass” to scratches, the effect will be temporary and visually unsatisfactory.
Will polishing remove all scratches?
Polishing removes defects in the varnish layer. If the scratch is deep and can be felt with your fingernail (reaches the ground or metal), polishing will not remove it, but will only make the edges less noticeable. Such defects require local touch-up.
How often should ceramic coating be renewed?
Modern professional ceramics last from 2 to 5 years. However, their hydrophobic properties may decrease earlier. To extend the life of the coating, it is recommended to use a maintenance spray activator (top-coat) based on SiO2 once every 3-4 months.